Methods and apparatus for controlling downhole drilling and completion configurations are growing more complex and there is an ever increasing need for downhole control systems which include downhole computerized modules employing downhole computers for commanding downhole tools such as packers, sliding sleeves, valves, etc. based on input from downhole sensors. It will be appreciated that these control systems utilize downhole devices and circuits that require electrical power. Because of shortcomings associated with providing electricity via a wireline from the surface or via batteries housed in the downhole environment, downhole electric power generators have been suggested for use to provide power for downhole electronics. When turbines are employed as the downhole electric power generator, the turbine blades are provided within the flow path of the borehole, obstructing full bore access so that wireline or other operations cannot be performed, such as entry of completion equipment and other objects into the tubing, downhole of the level of the turbine. Other downhole electric power generators including turbines have been provided on a side of the bore so as not to significantly obstruct the main flow, but require a diversion of flow to move the blades. The diverted flow may not be as powerful as the flow through the main flow and the size of the electric power generator must be smaller to fit on the side of the tubing, both of which inevitably reduce the potential capacity for electric power generation.